What is the Cyclocopter ?

The cyclocopter is a new VTOL (Vertical Take-Off and Landing) air vehicle that employs a unique propulsion system of cycloidal blade system to generate the propulsion and lift for a VTOL maneuver. The rotor system consists of several blades rotating about a horizontal axis that is perpendicular to the direction of normal flight. Picture on the right is a prototype of the cyclocopter and picture on the right below shows a typical pitch motion experienced by a blade on its rotating orbit.


Cycloidal Blade System

The rotor consists of several blades rotating about a horizontal axis perpendicular
to the direction of normal flight.

The cycloidal propeller offers powerful thrust levels, and a unique ability to change the direction of the thrust almost instantly.

The blade near the top and the bottom positions produces upward force with positive angle of attack but on the left and the right positions makes little forces since the blade has zero angle of attack.

The angle of the individual blades to the tangent of the circle of the blades path is varied by a pitch control mechanism so designed that the periodic oscillation of the blades about their span axis may be changed both in amplitude and in phase angle.


Cycloidal Curves

Advance ratio is defined as the ratio of the advance velocity to the rotational velocity

    a  >  b

  prolate cycloid trajectory

  pitch ratio >

  advance ratio > 1

   high-pitch motion

    a  =  b

  cycloid trajectory

  pitch ratio =

  advance ratio = 1

   -pitch motion

    a  <  b

  curtate cycloid trajectory

  pitch ratio <

  advance ratio < 1

   low-pitch motion